bonding: Advertize vxlan offload features when supported

When the underlying device supports TCP offloads for VXLAN/UDP
encapulated traffic, we need to reflect that through the hw_enc_features
field of the bonding net-device. This will cause the xmit path
in the core networking stack to provide bonding with encapsulated
GSO frames to offload into the HW etc.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -1025,10 +1025,14 @@ static netdev_features_t bond_fix_features(struct net_device *dev,
 				 NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \
 				 NETIF_F_HIGHDMA | NETIF_F_LRO)
 
+#define BOND_ENC_FEATURES	(NETIF_F_ALL_CSUM | NETIF_F_SG | NETIF_F_RXCSUM |\
+				 NETIF_F_TSO | NETIF_F_GSO_UDP_TUNNEL)
+
 static void bond_compute_features(struct bonding *bond)
 {
 	unsigned int flags, dst_release_flag = IFF_XMIT_DST_RELEASE;
 	netdev_features_t vlan_features = BOND_VLAN_FEATURES;
+	netdev_features_t enc_features  = BOND_ENC_FEATURES;
 	struct net_device *bond_dev = bond->dev;
 	struct list_head *iter;
 	struct slave *slave;
@@ -1044,6 +1048,9 @@ static void bond_compute_features(struct bonding *bond)
 		vlan_features = netdev_increment_features(vlan_features,
 			slave->dev->vlan_features, BOND_VLAN_FEATURES);
 
+		enc_features = netdev_increment_features(enc_features,
+							 slave->dev->hw_enc_features,
+							 BOND_ENC_FEATURES);
 		dst_release_flag &= slave->dev->priv_flags;
 		if (slave->dev->hard_header_len > max_hard_header_len)
 			max_hard_header_len = slave->dev->hard_header_len;
@@ -1054,6 +1061,7 @@ static void bond_compute_features(struct bonding *bond)
 
 done:
 	bond_dev->vlan_features = vlan_features;
+	bond_dev->hw_enc_features = enc_features;
 	bond_dev->hard_header_len = max_hard_header_len;
 	bond_dev->gso_max_segs = gso_max_segs;
 	netif_set_gso_max_size(bond_dev, gso_max_size);
@@ -3975,6 +3983,7 @@ void bond_setup(struct net_device *bond_dev)
 				NETIF_F_HW_VLAN_CTAG_FILTER;
 
 	bond_dev->hw_features &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_HW_CSUM);
+	bond_dev->hw_features |= NETIF_F_GSO_UDP_TUNNEL;
 	bond_dev->features |= bond_dev->hw_features;
 }